Heat is an undesirable by-product in the operation of electrical devices, such as, motors, generators, and transformers. Elevated operating temperatures can reduce device reliability and lifetime. The dissipation of heat also imposes constraints on device design and hinder the ability to achieve higher power density devices. Electrical insulation materials typically have low thermal conductivity, which can limit heat dissipation in electrical devices.
Polyethylene terephthalate films are widely used as electrical insulation within motors, generators, transformers, and many other applications. For higher performance applications, where higher temperature and/or higher chemical resistance are needed, polyimide films are used.